HVX - 'shifting' frames problem?

T

tduncan

Active member
I just returned from a shoot trip where I experienced a problem that I had never seen before.

While following a moving subject, the image will suddenly shift horizontally over the course of a couple of frames. It appears as though the tripod has been bumped. There will be a normal frame, a blurry 'shift' frame, then a normal frame with the whole image being shifted approx 1/10th of the total frame horizontally, then it resumes normally with the new position. It does this approx every 10 seconds or so.

I havent sat down to fully analyze what is happening but will today as we flew in late last night. I did step through a couple of clips to watch it and it definitely ruined the shots. Does this ring a bell for anyone?

thanks,
td
 
TD, it's most likely because you had the stablizer on. This has caught many people off guard and is simply the stablizer catching up.
Don't use the image stablizer on a tripod.
 
OIS would certainly explain what I am seeing. Should not be used while shooting surfing or any other action footage eh? Is Pannys OIS buggy? Never had a Canon do this and their IS seems flawless. I'll try to post some footage later today.

thanks,
tom
 
The OIS seems more powerful than on the DVX, but added this new "twitch". Nobody ever complained about it on the DVX, even though technically it can still happen, so I think it's when they juiced up the sensitivity of the OIS then this twitch came as an unintended consequence.
 
I always get this with Canon's Professional L series Lens for EOS cameras. If I forget to turn of IS when mounted on a tripod, long exposures turn out very blurry.
 
The OIS on Panny's seems tuned mostly for handheld shots that are supposed to be still. You point the camera and the OIS smooths out the random hand shakes. Doesn't work so well for shots where movement is intentional. It fights you every step of the way. Not sure how other manufacturers have designed their IS.
 
I have experienced this same problem with the Panasonic PV-GS65 (a 3-chip consumer cam).

I had a tripod shot where someone walked into frame and when they first broke the sensor edge the camera jumped several pixels one direction, then several pixels back to the starting position and then all was fine.
 
tduncan said:
OIS would certainly explain what I am seeing. Should not be used while shooting surfing or any other action footage eh?
tom
Click to expand...

OIS should not be used while the camera is on a tripod regardless of what you are shooting. It should only be turned on when doing hand held work.
 
I did experience this with OIS on. Other thing OIS adds when shooting 25p (I own the pal camera) is extra strobing on pans and tilts. I suggest that for movement shots (pans and tilts) on 25p and tripod to turn OIS off.
 
The HVX system looks like it is designed to deal with the vibration from hand-holding: this is relatively high-frequency and it takes place mostly in the x-y plane at right-angles to the lens axis. If you pan with OIS on, the camera clocks up all the x movements and keeps trying to adjust until it reaches the limit, then clicks back to its resting point (Barry explained this in an earlier post in another thread). Now, what Canon and Nikon have built into their IS systems for stills camera is a sensor which can detect a constant movement in one axis AND IGNORE IT. We don't have that on the HVX, and that's because (I think) the system is entirely optical - works by analyzing the video signal - and does not use an accelerometer which actually measures the shakes and wobbles directly.
 
yes Panny's OIS is buggy. Even though these glitches happen with still camera lenses, I've never seen it in video cameras. It's completely unacceptable. Let's hope they fix it till HVX200A.
 
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